1. Technical Field
The present invention relates to a piezoelectric actuator, piezoelectric motor, robot, hand, and pump.
2. Related Art
An piezoelectric actuator including a piezoelectric element for determination of a drive state of the piezoelectric element based on electric charge (detection signal) generated by the piezoelectric effect with driving of the piezoelectric element is known (e.g. see Patent Document 1 (JP-A-2008-199774)).
For example, an apparatus described in Patent Document 1 has state determination means for determining a state of a piezoelectric element based on a potential difference between both ends of a detection resistance provided in an electric circuit between the piezoelectric element and a ground point.
In the apparatus described in Patent Document 1, a circuit forming the state determination means is necessary with respect to each piezoelectric element, and, when a plurality of piezoelectric elements are used, there is a problem that downsizing is harder because a plurality of the circuits forming the state determination means are necessary and wiring connected to the state determination means is complex.